Explore pairing with plbstl/first-contribution for welcoming new contributors

[jeffreyksmithjr]

Per @melissawm's suggestion.

With #39 / #40, Good Egg now detects whether a PR author is new to the repo before deciding whether to run full scoring. plbstl/first-contribution solves the adjacent problem: automatically posting a welcome message (with labels and reactions) when someone opens their first issue or PR.

The two tools don't overlap. Good Egg scores trust, first-contribution posts greetings. But they share the same trigger condition and would work well together in a workflow. Worth exploring:

• Documentation: Add an example workflow (or a section in docs/github-action.md) showing both actions side by side. first-contribution welcoming the author and Good Egg scoring them in parallel.

• Conditional welcoming: first-contribution's output could gate whether Good Egg's comment is posted. For example, skip the trust score comment for a first-timer's first PR if you'd rather just welcome them, then score on subsequent PRs. Or the reverse: use Good Egg's skipped output to decide whether to show a welcome.

• Label coordination: first-contribution can apply labels like first-contribution. Good Egg could read those labels (or its own trust level) to apply complementary labels like needs-review for LOW trust authors.

No code changes required to make them work together today. This is about documenting the pattern and seeing if there's a tighter integration worth building.

Ref: https://github.com/plbstl/first-contribution